Name derivation:

Common name – ‘water shield’

Classification:

Brasenia Schreb.;at least 7 species are recognized (Fassett
1953).

Order Nympheales;Family Cabombaceae

Dicot

Morphology:

Suybmerged leaves are
highly dissected and reduced to an epidermal layer covering branched fascular
bundles.At the time of flowering,
floating leaves 6-12 cm long and 4-6 cm wide, with an entire outline, either
oval or narrow and forked, help support emergent flowers for aerial
pollination (Williamson and Schneider1993).Numerous
mucilage-secreting trichomes develop on the lower epidermal cells on the
underside of the leaves.

Turions (winter buds) are condensed
apical organs with a thick reddish stem, dwarf leaves with thick petioles,
and a coat of mucilage, are produced in early Fall.The turions abscise from the parent plant,
sink to the sediments, and germinate the following Spring (Williamson and
Schneider 1993).

Similar
genera:

Cabomba has a similar
flower development, especially in the initiation of the carpel based on SEM
analysis (Endress 2005).The structure
of the floaing leaves is also similar, including trichomes that secrete
mucilage on the underside.

Habitat:

Freshwater in the
tropics and subtropics of the ‘new world’.

References:

Endress, P.K.2005Carpels in Brasenia (Cabombaceae) are completely ascidiate despite a long
stigmatic crest.Annals of Botany
96:209-215.